1. Field of the Invention
The present invention relates to a motorcycle air cleaner system.
2. Background Art
FIG. 6 of the present application is a side elevation of a conventional air cleaner system. Fr represents the front of a vehicle body and Rr represents the rear of the vehicle body.
As shown in FIG. 6, a conventional motorcycle air cleaner system 100 has a single rear suspension damper 101 arranged close to the center of the vehicle body, a carburetor 102 arranged in front of the rear suspension damper 101, an air cleaner 103 arranged behind the rear suspension damper 101, and a connecting tube 104 connecting the carburetor 102 and the air cleaner 103. A front surface 103a of the air cleaner 103 is positioned substantially parallel to an axial line A of the rear suspension damper 101. The suspension damper 101 is moved backwards when fully compressed. Reference numeral 105 represents a main frame, reference numeral 106 represents a seat rail, and reference numeral 107 represents a subframe.
With the above structure, the connecting tube connecting the carburetor 102 and the air cleaner 103 is long, which has a detrimental effect on the performance of the engine. Also, the rear suspension damper 101 moves in the longitudinal direction of the vehicle, which means that the air cleaner 103 is positioned so that the rear suspension damper 101 can move. Accordingly, the capacity of the air cleaner is restricted, which lowers engine output.
An example of a motorcycle air cleaner system that shortens the connecting tube and also contributes to the capacity of the air cleaner is disclosed in Japanese Patent Publication No. Sho. 62-36909, entitled "Air Cleaner Assembly for Motorcycle."
As shown in FIG. 1 and FIG. 2 of that publication, an engine 14 is attached to a vehicle frame 10 (the reference numerals used in that publication will be used in this description). Carburetors 32, 32 are attached to the engine 24, an air chamber 30 is attached to the carburetors 32, 32 through connecting tubes 31, 31, and an air cleaner 33 is attached to the air chamber 30 through passages 44, 44, bypassing a shock absorber 22.
By this arrangement, a large quantity of air is drawn by an air retaining function of the air chamber 30. However, the air chamber 30 is arranged between the air cleaner 33 and the connecting tube, causing an increase in the number of components.
Also, because the air chamber 30 is positioned around the shock absorber 22, the structure becomes complicated and inspection and repair of the motorcycle is difficult.
It is therefore an object of the present invention to provide a motorcycle air cleaner system that can contribute to the capacity of an air cleaner without increasing the number of components and without a complicated structure.